A rhythmically pulsing leaf-spring DNA-origami nanoengine that drives a passive follower

Molecular engineering seeks to create functional entities for modular use in the bottom-up design of nanoassemblies that can perform complex tasks. Such systems require fuel-consuming nanomotors that can actively drive downstream passive followers. Most artificial molecular motors are driven by Brownian motion, in which, with few exceptions, the generated forces are non-directed and insufficient for efficient transfer to passive second-level components. Consequently, efficient chemical-fuel-driven nanoscale driver-follower systems have not yet been realized. Here we present a DNA nanomachine (70 nm × 70 nm × 12 nm) driven by the chemical energy of DNA-templated RNA-transcription-consuming nucleoside triphosphates as fuel to generate a rhythmic pulsating motion of two rigid DNA-origami arms. Furthermore, we demonstrate actuation control and the simple coupling of the active nanomachine with a passive follower, to which it then transmits its motion, forming a true driver-follower pair.

Reconfigurable Nanopolygons Made of DNA Catenanes

The development of new types of bonds and linkages that can reversibly tune the geometry and structural features of molecules is an elusive goal in chemistry. Herein, we report the use of catenated DNA structures as nanolinkages that can reversibly switch their angle and form different kinds of polygonal nanostructures. We designed a reconfigurable catenane that can self-assemble into a triangular or hexagonal structure upon addition of programmable DNA strands that function via toehold strand-displacement. The nanomechanical and structural features of these catenated nanojoints can be applied for the construction of dynamic systems such as molecular motors with switchable functionalities.

A Self-Regulating DNA Rotaxane Linear Actuator Driven by Chemical Energy

Nature-inspired molecular machines can exert mechanical forces by controlling and varying the distance between two molecular subunits in response to different inputs. Here, we present an automated molecular linear actuator composed of T7 RNA polymerase (T7RNAP) and a DNA [2]rotaxane. A T7 promoter region and terminator sequences are introduced into the rotaxane axle to achieve automated and iterative binding and detachment of T7RNAP in a self-controlled fashion. Transcription by T7RNAP is exploited to control the release of the macrocycle from a single-stranded (ss) region in the T7 promoter to switch back and forth from a static state (hybridized macrocycle) to a dynamic state (movable macrocycle). During transcription, the T7RNAP keeps restricting the movement range on the axle available for the interlocked macrocycle and prevents its return to the promotor region. Since this range is continuously depleted as T7RNAP moves along, a directional and active movement of the macrocycle occurs. When it reaches the transcription terminator, the polymerase detaches, and the system can reset as the macrocycle moves back to hybridize again to the ss-promoter docking site. The hybridization is required for the initiation of a new transcription cycle. The rotaxane actuator runs autonomously and repeats these self-controlled cycles of transcription and movement as long as NTP-fuel is available.

Impact of admission serum acid uric levels on in-hospital outcomes in patients with acute coronary syndrome

Background

Hyperuricemia has been associated with high mortality rates in patients with acute myocardial infarction. The role and the prognostic relevance of increased serum uric acid (SUA) in patients with acute coronary syndrome (ACS) are still under debate

Aim

We sought to assess the association between elevated admission levels of SUA and in-hospital adverse outcomes in a real-world patient population with ACS and to investigate the potential incremental prognostic value of SUA added to GRACE score

Methods

1088 consecutive patients admitted with a diagnosis of ACS to the Coronary Care Unit of two Hospitals were enrolled. Medical history, clinical characteristic, biochemical and electrocardiographic findings, angiographic data, treatments administered during hospitalization were all collected on an electronic database. All patients' data were entered prospectively in the database of the two hospitals and retrospectively analysed.

Results

The mean age was 68 years (IQR 60–78). Less than one-third of the total population was female (24%). Diabetes mellitus was present in 308 (28%) patients. The proportion of patients with STEMI and NSTEMI/UA was quite similar: 504 (46%) patients had a diagnosis of STEMI and 584 (54%) patients had a diagnosis of NSTEMI/UA. The GRACE score was 133 (IQR 112–156). In-hospital mortality rate was 2.3% in the overall population. Two variables were associated with a significantly increased risk of in-hospital death at the multivariate analysis: SUA (OR 1.72 95% CI 1.33–2.22, p<0.0001) and GRACE score (OR 1.04 95% CI 1.02–1.06, p<0.0001). To investigate the potential incremental prognostic value of SUA added to GRACE score for in-hospital death, we analyzed the results of adding hyperuricemia as categorical variable to the original GRACE risk model (GRACE-SUA score). The areas under the ROC curve (AUC) for GRACE score and for SUA were 0.91 (95% CI 0.89–0.93, p<0.0001) and 0.79 (95% CI 0.76–0.81, p<0.0001) respectively. The AUC was larger for predicting in-hospital mortality with the GRACE-SUA score (0.94; 95% CI 0.93–0.95; p<0.0001). The addition of hyperuricemia to the GRACE score led to reclassifying 18 of 211 (8.5%) patients without in-hospital deaths from high to low risk. No patients with o without events were incorrectly reclassified. The net-reclassification index (NRI) of the GRACE-SUA score was 1.7% (z value of 4.3; p<0.001).

Conclusions

High admission levels of SUA are positively and independently associated with in-hospital adverse outcomes and mortality in a contemporary and unselected population of ACS patients. The inclusion of SUA to GRACE risk score seems to lead to a more accurate prediction of in-hospital mortality and to improve risk classification in this study population.

Funding Acknowledgement

Type of funding source: None

Interlocked DNA Nanojoints for Reversible Thermal Sensing

The ability to precisely measure and monitor temperature at high resolution at the nanoscale is an important task for better understanding the thermodynamic properties of functional entities at the nanoscale in complex systems, or at the level of a single cell. However, the development of high-resolution and robust thermal nanosensors is challenging. The design, assembly, and characterization of a group of thermal-responsive deoxyribonucleic acid (DNA) joints, consisting of two interlocked double-stranded DNA (dsDNA) rings, is described. The DNA nanojoints reversibly switch between the static and mobile state at different temperatures without a special annealing process. The temperature response range of the DNA nanojoint can be easily tuned by changing the length or the sequence of the hybridized region in its structure, and because of its interlocked structure the temperature response range of the DNA nanojoint is largely unaffected by its own concentration; this contrasts with systems that consist of separated components.

Efficacy and safety of HAT1 compared with calcipotriol in the treatment of patients with mild to moderate chronic plaque psoriasis: results from an open-label randomized comparative pilot clinical study

Psoriasis is commonly treated with topical corticosteroids, oral cytotoxic drugs and biologic agents, which can be associated with significant adverse effects (AEs), high cost and response attenuation. Additionally, patients often use alternative therapies ad hoc, which can be challenging to integrate into a treatment regimen, owing to a lack of adequately powered controlled trials assessing efficacy and safety. We developed a novel topical botanical complex, herbal anti‐inflammatory treatment (HAT1), through extensive preclinical in vitro and in vivo modelling to define key mechanisms of action and clinical potential. To assess the efficacy and safety of HAT1 in psoriasis, we performed a 10‐week, open‐label, pilot clinical trial comparing topical treatment of HAT1 with calcipotriol 0.005% in adult patients with mild to moderate psoriasis. Primary and secondary endpoints included the percentage of patients obtaining improvement of ≥ 75% in Psoriasis Area and Severity Index (PASI 75), Physician’s Global Assessment (PGA) response, and evaluation of tolerability and safety of HAT1. In the HAT1 arm, 85.7% of study patients reached PASI 75 compared with 21.4% in the calcipotriol comparator group. Additionally, 78.6% of patients in the HAT1 arm achieved a ‘clear’ or ‘minimal’ PGA response. HAT1 was well tolerated, with no AEs observed throughout the trial. These results suggest that HAT1 reduces psoriasis disease activity in a clinically relevant manner. Ongoing studies, including well‐powered, double‐blind, randomized controlled trials will be required to assess the potential of HAT1 in psoriasis.

Advances in below-the-knee drug-eluting balloons

The management of critical limb ischemia due to below-the-knee disease remains challenging due to the frequent patient comorbidities, diffuse vascular involvement, and high rates of restenosis and disease progression. The BASIL study has established the substantial equivalence between bypass surgery and percutaneous transluminal angioplasty in this setting, at least at mid-term follow-up, but percutaneous techniques and devices have seen major developments since the publication of this pivotal trial in 2005. A major breakthrough has indeed been the introduction of drug-eluting balloons, which have several theoretical advantages in comparison to standard balloons and metallic stents for infra-popliteal lesions. Two clinical trials have already been reported with favorable results for the In.Pact Amphirion paclitaxel-eluting balloon, when employed for below-the-knee lesions. We hereby discuss the rationale for the use of drug-eluting balloons in this complex setting and the main findings of the study by Schmidt et al. and the DEBATE-BTK trial.

Combining electrospinning and fused deposition modeling for the fabrication of a hybrid vascular graft

Tissue engineering of blood vessels is a promising strategy in regenerative medicine with a broad spectrum of potential applications. However, many hurdles for tissue-engineered vascular grafts, such as poor mechanical properties, thrombogenicity and cell over-growth inside the construct, need to be overcome prior to the clinical application. To surmount these shortcomings, we developed a poly-L-lactide (PLLA)/poly-epsilon-caprolactone (PCL) scaffold releasing heparin by a combination of electrospinning and fused deposition modeling technique. PLLA/heparin scaffolds were produced by electrospinning in tubular shape and then fused deposition modeling was used to armor the tube with a single coil of PCL on the outer layer to improve mechanical properties. Scaffolds were then seeded with human mesenchymal stem cells (hMSCs) and assayed in terms of morphology, mechanical tensile strength, cell viability and differentiation. This particular scaffold design allowed the generation of both a drug delivery system amenable to surmount thrombogenic issues and a microenvironment able to induce endothelial differentiation. At the same time, the PCL external coiling improved mechanical resistance of the microfibrous scaffold. By the combination of two notable techniques in biofabrication--electrospinning and FDM--and exploiting the biological effects of heparin, we developed an ad hoc differentiating device for hMSCs seeding, able to induce differentiation into vascular endothelium.

Ablation of Stat3 by siRNA alters gene expression profiles in JEG-3 cells: a systems biology approach

Control of inflammation at the maternal-fetal interface is a critical element in mammalian pregnancy. Previous work from our laboratory has shown that Stat3 may be a placental mediator involved in maintaining immunologic homeostasis at the maternal-fetal interface. The aim of the current study is to further elucidate the role of Stat3 in response to inflammation. As ablation of Stat3 in mice results in embryonic lethality, we evaluated the role of Stat3 in vitro using an siRNA approach. Trophoblast-like JEG-3 cells were transfected with an siRNA construct specific to Stat3. Experimental and control cells were exposed to conditioned medium from PHA-activated peripheral blood mononuclear cells and incubated for 45 min. Cells were then collected and RNA isolated for transcriptional profiling using human Affymetrix U133 plus 2.0 GeneChips. Differences in gene expression between control and Stat3-ablated cells were evaluated using conventional statistical methods. Fifty-two genes were detected as up-regulated in conditioned medium in both mock transfected and in Stat3 siRNA transfected JEG-3 cells. Two genes (EPAS1 and RASGEF1B) were up-regulated only in cells transfected with negative control siRNA, while 36 genes were up-regulated only in cells transfected with Stat3 siRNA. Sixty genes were differentially expressed between Stat3 siRNA transfected cells relative to mock transfected cells both in basal and conditioned medium. These included 31 genes up-regulated with Stat3 siRNA transfected cells and 29 genes down-regulated with Stat3 siRNA. Eleven genes were differentially expressed only in basal medium. Seven of these were up-regulated in the presence of Stat3 siRNA and four were down-regulated. Nine genes were differentially expressed only in conditioned medium. Six of these were up-regulated and three down-regulated in the presence of Stat3 siRNA. Off-target effects were excluded in a second set of experiments in which Stat3 mRNA was targeted at a different site and quantitative real-time PCR performed on selected genes derived from the microarray analysis. While some of the genes that showed differential expression between Stat3-ablated cells and mock transfected controls were genes typically associated with immune response (e.g., CCR7 and IRAK1), in silico modeling of the microarray data also revealed complex networks of signaling molecules and molecules associated with cellular metabolism previously seen in transcription factor ablation in model organisms. We conclude thus: Stat3 controls a specific gene set in trophoblast-like JEG-3 cells. While some differentially expressed genes and in silico models of their functions are consistent with the hypothesis that Stat3 plays a role in regulating inflammation, Stat3-mediated response to inflammation appears to also involve complex homeostatic adaptations of a non-immunologic nature.

Multiplex serum cytokine monitoring as a prognostic tool in rheumatoid arthritis

OBJECTIVE

Early optimized therapy of rheumatoid arthritis (RA) results in improved outcomes. The initiation of optimized therapy is hindered by the difficulty of early diagnosis and the limitations of current disease activity and therapeutic response assessment tools. Identifying patients requiring early combination DMARD/biologic therapy is currently a significant clinical challenge given the lack of definitive prognostic criteria. Since cytokines are soluble intracellular signaling molecules that modulate disease pathology in RA, we tested the recent conjecture that en mass serum cyto-kine measurement and monitoring will provide a useful tool for effective therapeutic management in RA.

METHODS

We assayed the levels of 16 serum cytokines in 18 RA patients treated prospectively with methotrexate and from 18 unaffected controls. Specific mechanistic aspects of inflammatory pathology in the periphery could be discerned on a patient-specific basis from patients' serum cytokine profiles, information that may aid in the design of anti-cytokine biologic therapy. A serum Cytokine Activity Index (CAI) was also created using multi-variant analysis methods.

RESULTS

Distinct cytokines were significantly elevated in RA patients relative to controls, and three distinct clusters with correlations to disease activity were identified. The Cytokine Activity Index correlated well with the therapeutic res-ponse; responders and non-responders in this cohort were distinguishable as early as one month post initiation of methotrexate therapy, well before clinical assessments of response are commonly completed.

CONCLUSION

Clinical assessment tools could be derived from this approach that may provide a means to continually track patients, allowing intervention strategies to be better evaluated on a patient-specific basis and to identify residual cytokine activity that could be used to guide combination therapy.

Circulating cytokines in Norwegian patients with psoriatic arthritis determined by a multiplex cytokine array system

OBJECTIVES

Serum cytokines play an important role in the pathogenesis of psoriatic arthritis (PsA) by initiating and perpetuating various cellular and humoral autoimmune processes. The aim of this study was to describe a broad spectrum of T- and B-cell cytokines, growth factors and chemokines in patients with PsA and healthy individuals.

METHODS

A novel protein array system, denoted as multiplex cytokine assay was utilized to measure simultaneously the levels of 23 circulating cytokines of patients with PsA and healthy individuals. Additionally, correlational clustering and discriminant function analysis (DFA), two multivariate, supervised analysis methods were employed to identify a subset of biomarkers in order to describe potential functional inter-relationships among these pathological cytokines and identify biomarkers with prognostic and diagnostic utility.

RESULTS

Univariate analysis demonstrated that serum levels of a complex set of immune and inflammatory modulating cytokines are significantly up-regulated in patients with PsA relative to unaffected controls including interleukin (IL)-10, IL-13, interferen (IFN)-alpha, epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), fibroblast growth factor [CCL3 macrophage inflammatory protein (MIP)-1alpha], CCL4 (MIP-1beta) and CCL11 (Eotaxin), while granulocyte-colony stimulating factor was significantly reduced in PsA patients. Correlational clustering was able to discriminate among, and hence subclassify, patients with varying levels of disease activity, which may prove useful in guiding therapy in these apparently phenotypically distinct disease subsets. DFA identified EGF, IFN-alpha, VEGF, CCL3 (MIP-1alpha) and IL-12p40 as analytes with the strongest discriminatory power among various PsA patients and controls.

CONCLUSIONS

Our findings suggest that these factors modulate PsA pathology and the articular involvement in a synergistic manner. Identifying factors could be used in the development of clinical diagnostic tests, which are valuable to guide evidence-based diagnosis and disease management of PsA.

Genome-scale Assessment of Molecular Pathology in Systemic Autoimmune Diseases using Microarray Technology: A Potential Breakthrough Diagnostic and Individualized Therapy-design Tool

Systemic autoimmune rheumatic diseases are of complex aetiology, characterized by an intricate interplay of various factors. A myriad of genes lies behind the heterogeneous manifestations of these diseases, and the overexpression and repression of particular genes form a specific gene-expression profile (genetic fingerprints) that is characteristic to the given disease phenotype. Besides the description of various cell types by using gene-expression profiling, the data should be directly applicable to the design of individual therapeutic protocols for patients suffering from various autoimmune diseases. In this review, we summarize the gene-expression profile, various genetic signatures of different autoimmune diseases and give an overview on the possible interpretations of the data. The application of recent breakthroughs in high-throughput molecular profiling technologies, such as microarray technology has been the basis for a revolution in biomedical research, as well as diagnostics and pharmaceutical development. It is easy to envision a day when personalized medicine, which is the diagnosis and treatment of a given patient with agents and procedures tailored to that patient's genetics, physiology and pathology, will become the standard of care.

A genome-scale assessment of peripheral blood B-cell molecular homeostasis in patients with rheumatoid arthritis

OBJECTIVE

While rheumatoid arthritis (RA) is considered a prototypical autoimmune disease, the specific roles of B-cells in RA pathogenesis is not fully delineated.

METHODS

We performed microarray expression profiling of peripheral blood B-cells from RA patients and controls. Data were analysed using differential gene expression analysis and 'gene networking' analysis (characterizing clusters of functionally inter-relelated genes) to identify both regulatory genes and the pathways in which they participate. Results were confirmed by quantitative real-time polymerase chain reaction and by measuring the levels of 10 serum cytokines involved in the pathways identified.

RESULTS

Genes regulating and effecting the cell-cycle, proliferation, apoptosis, autoimmunity, cytokine networks, angiogenesis and neuro-immune regulation were differentially expressed in RA B-cells. Moreover, the serum levels of several soluble factors that modulate these pathways, including IL-1beta, IL-5, IL-6, IL-10, IL-12p40, IL-17 and VEGF were significantly increased in this cohort of RA patients.

CONCLUSIONS

These results outline aspects of the multifaceted role B-cells play in RA pathogenesis in which immune dysregulation in RA modulates B-cell biology and thereby contributes to the induction and perpetuation of a pathogenic humoral immune response.

Transcriptional modulation of TCR, Notch and Wnt signaling pathways in SEB-anergized CD4+ T cells

Gene expression changes in CD4 + Vbeta8+ T cells energized by in vivo exposure to staphylococcal enterotoxin B (SEB) bacterial superantigen compared to CD4 + Vbeta8+ non-energic T cells were assessed using DNA microarrays containing 5184 murine complementary DNAs. Anergy in splenic T cells of SEB-immunized BALB/c mice was verified by dramatically reduced proliferative capacity and an 8 x overexpression of GRAIL mRNA in CD4 + Vbeta8+ T cells taken from mice 7 days after injection. At an Associative t-test threshold of P<0.0005, 96 genes were overexpressed or detected only in anergic T cells, while 256 genes were suppressed or not detected in anergic T cells. Six of eight differential expressions tested using real-time quantitative PCR were validated. Message for B-Raf was detected only in non-anergic cells, while expression of the TCR signaling modulator Slap (Src-like adapter protein) and the TCR zeta-chain specific phosphatase Ptpn3 was enhanced. Modulation of multiple genes suggests downregulation of Wnt/beta-catenin signaling and enhanced Notch signaling in the anergic cells. Consistent with previous reports in a non-superantigen in vivo anergy model, mRNA for CD18 and the transcription factor Satb1 (special AT-rich-binding protein 1) was increased in SEB-energized T cells. This is the first report of global transcriptional changes in CD4+ T cells made anergic by superantigen exposure.

Mobile classification in microarray experiments

In a homogeneous group of samples, there are genes whose expression variations can be attributed to factors other than experimental errors. These factors can include natural biological oscillations or metabolic processes. These genes are rarely classified as 'interesting' based on their variability profile. However, their dynamic behaviour can tease out important clues about naturally occurring biological processes in the organism under study and can be used for group classification. Dynamical discriminate function analysis was developed on the concept that stable classification parameters (roots) can be derived from highly variable gene-expression data. Stability of these combinations implies a strongly compensatory relationship that may divulge functional interconnections.

5alpha-Androstane-3alpha,17beta-diol activates pathway that resembles the epidermal growth factor responsive pathways in stimulating human prostate cancer LNCaP cell proliferation

5alpha-Androstane-3alpha,17beta-diol (3alpha-diol) is considered to have no androgenic effects in androgen target organs unless it is oxidized to 5alpha-dihydrotestosterone (5alpha-DHT). We used microarray and bioinformatics to identify and compare 3alpha-diol and 5alpha-DHT responsive gene in human prostate LNCaP cells. Through a procedure called 'hypervariable determination', a similar set of 30 responsive genes involving signal transduction, transcription regulation, and cell proliferation were selected in 5alpha-DHT-, 3alpha-diol-, and epidermal growth factor (EGF)-treated samples. F-means cluster and networking procedures showed that the responsive pattern of these genes was more closely related between 3alpha-diol and EGF than between 5alpha-DHT and 3alpha-diol treatments. We conclude that 3alpha-diol is capable of stimulating prostate cell proliferation by eliciting EGF-like pathway in conjunction with androgen receptor pathway.

Apoptotic Effect of Rituximab on Peripheral Blood B Cells in Rheumatoid Arthritis

Rituximab (RTX) has proven efficacious in the treatment of rheumatoid arthritis (RA). Herein, we assessed the apoptosis-inducing capability of RTX in vitro on RA peripheral blood B-cell subsets and also compared the effects of RTX on B cells from rheumatoid factor-positive (RF+) and RF- patients. The likely relevance of B cells in disease was assessed by measuring B-cell-modulating serum cytokines. Peripheral blood B cells were isolated and cultured with the presence or absence of RTX. The levels of apoptosis within the naïve, memory and IgD+CD27+ B-cell subpopulations were determined by cytofluorometric analysis and caspase 3/7 assays. Levels of serum cytokines were measured with a multiplex cytokine array system. RTX induced significant apoptosis in all B-cell subsets in both RA and controls. In naïve and memory B cells from RA patients, RTX induced significantly higher levels of apoptosis than in controls. RTX induced apoptosis of B cells in RF+ and RF- patients. Serum levels of interleukin-1beta (IL-1beta), IL-4, IL-10 and IL-13 were profoundly increased in RF+ patients compared to RF- patients and controls. Although our cohort was small (10 RA patients), the data suggest that RTX induces apoptosis in all investigated subsets of B cells from RA patients. Interestingly, memory B cells from RA patients were more sensitive to RTX than memory cells from normal controls, suggesting that the delay in treatment response to RTX observed in clinical trials may be due in part to memory cell depletion. The apoptotic effects of RTX were similar in RF+ and RF- patients, but serum levels of B-cell-activating cytokine levels were only elevated in RF+ but not RF- patients. These data suggest that RTX is less effective in RF- RA because B cells play a less significant role in RA pathogenesis in RF- patients.

Circulating cytokines in primary Sjögren's syndrome determined by a multiplex cytokine array system

Plasma cytokines play an important role in the pathogenesis of Sjögren's syndrome (SS) by initiating and perpetuating various cellular and humoural autoimmune processes. The aim of the present study was to describe a broad spectrum of T-cell and B-cell cytokines, growth factors, chemokines and molecules that could contribute to cell death in SS. A novel protein array system was utilized to measure simultaneously the levels of 25 plasma cytokines of patients with primary SS and healthy individuals. Furthermore, we correlated these plasma cytokine levels with potential laboratory and clinical parameters related to disease activity in SS. A subset of plasma cytokines [e.g. interleukin-1beta (IL-1beta), IL-6, CXCL8 (IL-8), IL-12 p40, IL-15, tumour necrosis factor-alpha (TNF-alpha), epidermal growth factor, CCL4 (MIP-1beta), CCL2 (MCP-1), CCL11 (Eotaxin), CCL5 (RANTES), TNF-RI and TNF-RII] was found to significantly differ between patients and controls. Also, distinct populations of cytokines were found to differentiate between patients with normal versus elevated ESR or IgG levels and patients with the presence or absence of extra-glandular manifestations (EGMs). Our results support the assumption that the multiplex cytokine array system can be successfully utilized in the diagnosis and disease management of SS. Furthermore, it may provide a powerful tool in the design of individualized anticytokine therapies.

Characterization of viable autofluorescent macrophages among cultured peripheral blood mononuclear cells

BACKGROUND

Inflammatory macrophages that demonstrate intense autofluorescence have been isolated directly from alveolar and peritoneal tissues, but their generation in vitro remains vague. We use flow cytometry to identify a population of autofluorescent macrophages as they arise among nonadherent populations of cultured blood mononuclear cells.

METHODS

Cells were obtained from donated blood buffy coats and placed in culture for 14 days. Unstained populations from the cells remaining in suspension were sampled daily using flow cytometry. During the first 5 culture days, a distinct population of autofluorescent cells arose and comprised an average of < or =14% of the total cell population. This population declined to less than 6% by culture day 8.

RESULTS

The cells were identified as viable macrophages expressing CD68, lysozyme, and HLA-DR. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) demonstrated a unique cytokine profile with IL-1 alpha expression levels 138-fold higher than those measured in uncultured monocytes. No significant elevation in the levels of other cytokines was identified. Upon replating, the sorted populations became readherent, were able to ingest plastic beads, and remained viable for 6 or more additional weeks in culture without evidence of proliferation or multinucleation.

CONCLUSION

Viable autofluorescent macrophage populations arising among cultured peripheral blood may be easily identified and isolated for further study using flow cytometry. Cytometry 44:38-44, 2001. Published 2001 Wiley-Liss, Inc.

Isolation, genomic organization, and expression analysis of the mouse and rat homologs of MEFV, the gene for familial mediterranean fever

Familial Mediterranean fever (FMF) is a recessive disorder characterized by episodes of fever with serositis or synovitis. Recently the FMF gene (MEFV) was cloned; the protein product, pyrin/marenostrin, is thought to regulate inflammation in myeloid cells. In this manuscript we report the mouse and rat homologs of MEFV. The murine gene contains ten exons with a coding sequence of 2304 bp, while the rat homolog has nine exons with a coding sequence of 2253 bp. A considerable amino acid sequence homology was observed between the mouse and human (47.6% identity and 65.5% similarity) and between the mouse and rat genes (73.5% identity and 82.1% similarity). The predicted rodent proteins have several important domains and signals found in human pyrin, including a B-box zinc finger domain, Robbins-Dingwall nuclear localization signal, and coiled-coil domain. However, perhaps because of an ancient frame-shift mutation, neither the mouse nor the rat protein has an intact C-terminal B30.2 domain, in which most FMF-associated mutations have been found in human MEFV. Nevertheless, like the human gene, mouse Mefv is expressed in peripheral blood granulocytes but not lymphocytes. Consistent with its expression in granulocytes, Mefv was detected at high levels in the primary follicles and marginal zones of the splenic white pulp. Mefv is localized on mouse Chromosome (Chr) 16, region A3-B1, extending a region of synteny with human Chr 16p13.3. Development of knockout and knockin mouse models may provide further insights into the functional evolution of this gene.

The gene for familial Mediterranean fever, MEFV, is expressed in early leukocyte development and is regulated in response to inflammatory mediators

Familial Mediterranean fever (FMF) is a recessive disorder characterized by episodes of fever and neutrophil-mediated serosal inflammation. We recently identified the gene causing FMF, designated MEFV, and found it to be expressed in mature neutrophils, suggesting that it functions as an inflammatory regulator. To facilitate our understanding of the normal function of MEFV, we extended our previous studies. MEFV messenger RNA was detected by reverse transcriptase-polymerase chain reaction in bone marrow leukocytes, with differential expression observed among cells by in situ hybridization. CD34 hematopoietic stem-cell cultures induced toward the granulocytic lineage expressed MEFV at the myelocyte stage, concurrently with lineage commitment. The prepromyelocytic cell line HL60 expressed MEFV only at granulocytic and monocytic differentiation. MEFV was also expressed in the monocytic cell lines U937 and THP-1. Among peripheral blood leukocytes, MEFV expression was detected in neutrophils, eosinophils, and to varying degrees, monocytes. Consistent with the tissue specificity of expression, complete sequencing and analysis of upstream regulatory regions of MEFV revealed homology to myeloid-specific promoters and to more broadly expressed inflammatory promoter elements. In vitro stimulation of monocytes with the proinflammatory agents interferon (IFN) gamma, tumor necrosis factor, and lipopolysaccharide induced MEFV expression, whereas the antiinflammatory cytokines interleukin (IL) 4, IL-10, and transforming growth factor beta inhibited such expression. Induction by IFN-gamma occurred rapidly and was resistant to cycloheximide. IFN-alpha also induced MEFV expression. In granulocytes, MEFV was up-regulated by IFN-gamma and the combination of IFN-alpha and colchicine. These results refine understanding of MEFV by placing the gene in the myelomonocytic-specific proinflammatory pathway and identifying it as an IFN-gamma immediate early gene.

Stat4 is expressed in activated peripheral blood monocytes, dendritic cells, and macrophages at sites of Th1-mediated inflammation

Stat4 is a key transcription factor involved in promoting cell-mediated immunity, whose expression in mature cells has been reported to be restricted to T and NK cells. We demonstrate here, however, that Stat4 expression is not restricted to lymphoid cells. In their basal state, monocytes do not express Stat4. Upon activation, however, IFN-gamma- and LPS-treated monocytes and dendritic cells express high levels of Stat4. Monocyte-expressed Stat4 in humans is phosphorylated in response to IFN-alpha, but not IL-12. In contrast, the Th2 cytokines, IL-4 and IL-10, specifically down-regulate Stat4 expression in activated monocytes, while having little effect on Stat6 expression. Moreover, macrophages in synovial tissue obtained from patients with rheumatoid arthritis express Stat4 in vivo, suggesting a potential role in a prototypical Th1-mediated human disease. IFN-alpha-induced Stat4 activation in human monocytes represents a previously unrecognized signaling pathway at sites of Th1 inflammation.

Non-type I cystinuria caused by mutations in SLC7A9, encoding a subunit (bo,+AT) of rBAT

Cystinuria (MIM 220100) is a common recessive disorder of renal reabsorption of cystine and dibasic amino acids. Mutations in SLC3A1, encoding rBAT, cause cystinuria type I (ref. 1), but not other types of cystinuria (ref. 2). A gene whose mutation causes non-type I cystinuria has been mapped by linkage analysis to 19q12-13.1 (Refs 3,4). We have identified a new transcript, encoding a protein (bo, +AT, for bo,+ amino acid transporter) belonging to a family of light subunits of amino acid transporters, expressed in kidney, liver, small intestine and placenta, and localized its gene (SLC7A9) to the non-type I cystinuria 19q locus. Co-transfection of bo,+AT and rBAT brings the latter to the plasma membrane, and results in the uptake of L-arginine in COS cells. We have found SLC7A9 mutations in Libyan-Jews, North American, Italian and Spanish non-type I cystinuria patients. The Libyan Jewish patients are homozygous for a founder missense mutation (V170M) that abolishes b o,+AT amino-acid uptake activity when co-transfected with rBAT in COS cells. We identified four missense mutations (G105R, A182T, G195R and G295R) and two frameshift (520insT and 596delTG) mutations in other patients. Our data establish that mutations in SLC7A9 cause non-type I cystinuria, and suggest that bo,+AT is the light subunit of rBAT.

Clonal characteristics of T cell infiltrates in skin and synovium of patients with psoriatic arthritis

Psoriasis is a chronic inflammatory skin disease that is often complicated by an inflammatory arthritis. Considerable evidence implicates cellular immune responses in psoriatic skin lesions, but the pathogenesis of the associated arthritis has not been elucidated. We analyzed T cell antigen receptor beta chain variable (TCRbetaV) gene repertoires among peripheral blood lymphocytes, skin and synovium of nine patients with psoriatic arthritis. RNase protection assays were used to quantitate the expression levels of 25 TCRbetaV genes, and CDR3 region sequencing was used to further characterize selected expansions. All patients exhibited significant TCRbetaV biases in the peripheral blood and moreover, all had expansions common to both skin and synovium. CDR3 sequencing demonstrated these expansions frequently consisted of oligo- or monoclonal populations. Although no ubiquitous CDR3 nucleotide sequences were identified, two patients shared identical sequences and several highly homologous amino acid motifs were present in skin and synovium among and between individual patients. Findings of common TCRbetaV expansions in diverse inflammatory sites, among multiple afflicted individuals, suggest that these T cell proliferations are driven by engagements with a limited set of conventional antigens. These findings demonstrate an important role for cognate T cell responses in the pathogenesis of psoriatic arthritis, and further suggest the inciting antigen(s) is identical or homologous between afflicted skin and synovium.

Germline mutations in the extracellular domains of the 55 kDa TNF receptor, TNFR1, define a family of dominantly inherited autoinflammatory syndromes

Autosomal dominant periodic fever syndromes are characterized by unexplained episodes of fever and severe localized inflammation. In seven affected families, we found six different missense mutations of the 55 kDa tumor necrosis factor receptor (TNFR1), five of which disrupt conserved extracellular disulfide bonds. Soluble plasma TNFR1 levels in patients were approximately half normal. Leukocytes bearing a C52F mutation showed increased membrane TNFR1 and reduced receptor cleavage following stimulation. We propose that the autoinflammatory phenotype results from impaired downregulation of membrane TNFR1 and diminished shedding of potentially antagonistic soluble receptor. TNFR1-associated periodic syndromes (TRAPS) establish an important class of mutations in TNF receptors. Detailed analysis of one such mutation suggests impaired cytokine receptor clearance as a novel mechanism of disease.

Mutation and haplotype studies of familial Mediterranean fever reveal new ancestral relationships and evidence for a high carrier frequency with reduced penetrance in the Ashkenazi Jewish population

Familial Mediterranean fever (FMF) is a recessive disorder characterized by episodes of fever with serositis or synovitis. The FMF gene (MEFV) was cloned recently, and four missense mutations were identified. Here we present data from non-Ashkenazi Jewish and Arab patients in whom we had not originally found mutations and from a new, more ethnically diverse panel. Among 90 symptomatic mutation-positive individuals, 11 mutations accounted for 79% of carrier chromosomes. Of the two mutations that are novel, one alters the same residue (680) as a previously known mutation, and the other (P369S) is located in exon 3. Consistent with another recent report, the E148Q mutation was observed in patients of several ethnicities and on multiple microsatellite haplotypes, but haplotype data indicate an ancestral relationships between non-Jewish Italian and Ashkenazi Jewish patients with FMF and other affected populations. Among approximately 200 anonymous Ashkenazi Jewish DNA samples, the MEFV carrier frequency was 21%, with E148Q the most common mutation. Several lines of evidence indicate reduced penetrance among Ashkenazi Jews, especially for E148Q, P369S, and K695R. Nevertheless, E148Q helps account for recessive inheritance in an Ashkenazi family previously reported as an unusual case of dominantly inherited FMF. The presence of three frequent MEFV mutations in multiple Mediterranean populations strongly suggests a heterozygote advantage in this geographic region.

Identification and characterization of a zinc finger gene (ZNF213) from 16p13.3

During our search for the familial Mediterranean fever (FMF) gene, we identified by cDNA selection a 1.2 kb cDNA fragment representing a novel human gene that is expressed in a wide variety of tissues. This gene spans approx. 8.0 kb genomic DNA and has seven exons. Its 3' untranslated region contains a long tandem repeat that gives rise to a polymorphism with two alleles of approx. 1.1 kb and 1.0 kb, with the 1.1 kb allele in strong linkage disequilibrium with FMF in patients of different ethnic backgrounds. However, both genetic and mutational analyses have excluded this gene as the one responsible for FMF. The predicted 424 amino acid protein, designated ZNF213, contains three C2H2 zinc fingers, a Kruppel associated A box and a leucine rich motif (LeR domain/SCAN box), strongly suggestive of a transcription factor.

Characterization of gene expression in resting and activated mast cells

To characterize gene expression in activated mast cells more comprehensively than heretofore, we surveyed the changes in genetic transcripts by the method of serial analysis of gene expression in the RBL-2H3 line of rat mast cells before and after they were stimulated through their receptors with high affinity for immunoglobulin E (FcepsilonRI). A total of 40,759 transcripts derived from 11,300 genes were analyzed. Among the diverse genes that had not been previously associated with mast cells and that were constitutively expressed were those for the cytokine macrophage migration inhibitory factor neurohormone receptors such as growth hormone- releasing factor and melatonin and components of the exocytotic machinery. In addition, several dozen transcripts were differentially expressed in response to antigen-induced clustering of the FcepsilonRI. Included among these were the genes for preprorelaxin, mitogen-activated protein kinase kinase 3, and the dual specificity protein phosphatase, rVH6. Significantly, the majority of genes differentially expressed in this well-studied model of mast cell activation have not been identified before this analysis.

Identification of two Krüppel-related zinc finger genes (ZNF200 and ZNF210) from human chromosome 16p13.3

During the course of cloning the gene for familial Mediterranean fever (FMF), we identified a number of transcripts from a 275-kb genomic region on 16p13.3. Two of the transcripts were found to contain multiple C2H2-type zinc finger motifs in tandem arrays, indicating that they are members of the Krüppel-type family. One transcript was found to be an alternatively spliced form of a previously reported zinc finger gene, ZNF200. The other transcript, ZNF210, is 2017 bp and encodes an open reading frame of 504 aa. Northern blot analysis indicates that ZNF210 is expressed in all the tissues tested with the highest expression in heart, skeletal muscle, pancreas, prostate, ovary, and colon. On the other hand, the strongest expression of ZNF200 is in testis, with very low levels in all the other tissues tested. Sequence analysis reveals eight C2H2 zinc finger motifs at the C-terminus of ZNF210 and five in ZNF200. In addition, ZNF210 also possesses a Krüppel-associated box at its N-terminus, indicating that it might function as a transcription repressor. The intron-exon structures of both genes were determined and showed that ZNF210 has seven exons while the coding part of ZNF200 is distributed in four exons. The locations of ZNF200 and ZNF210 are 10 and 120 kb telomeric to the FMF gene, respectively.

The hereditary periodic fever syndromes: molecular analysis of a new family of inflammatory diseases

The hereditary periodic fever syndromes are a group of Mendelian disorders characterized by episodic fever and serosal or synovial inflammation. Familial Mediterranean fever (FMF) and the hyperimmunoglobulinemia D and periodic fever syndrome are both recessively inherited, while three dominantly inherited syndromes have been described, the best-characterized of which is familial Hibernian fever (FHF). The last year has seen two major developments in this field: the FMF gene was identified on chromosome 16p by positional cloning, and a second major periodic fever locus was mapped to distal chromosome 12p. The FMF gene (MEFV) encodes a novel 781 amino acid protein; to date, eight different missense mutations and a number of polymorphisms have been described. Seven of the eight mutations occur within a region of 82 amino acids near the C-terminus. Computational analysis of the conceptual protein reveals five different domains/motifs compatible with a nuclear effector function. MEFV is expressed preferentially in granulocytes and myeloid bone marrow precursors, giving rise to speculation that the protein may serve as a transcriptional regulator of inflammation in granulocytes. The second periodic fever locus was mapped by two different groups: one studying FHF, the other studying a similar dominantly inherited syndrome designated familial periodic fever. Both genes map to the same 19 cM region on distal chromosome 12p, strongly suggesting a common locus. The molecular characterization of the periodic fever genes should provide important new insights into the regulation of inflammation in general.

Familial Mediterranean fever at the millennium. Clinical spectrum, ancient mutations, and a survey of 100 American referrals to the National Institutes of Health

Regarded as the most common and best understood of the hereditary periodic fever syndromes, familial Mediterranean fever (FMF) is a recessively inherited disease of episodic fever with some combination of severe abdominal pain, pleurisy, arthritis, and a characteristic ankle rash. The flares typically last for up to 3 days at a time, and most patients are completely asymptomatic between attacks; if untreated with prophylactic colchicine, some patients later develop amyloidosis and renal failure. The recent cloning of the FMF gene on the short arm of chromosome 16p, and the subsequent finding that its tissue expression is limited to granulocytes, has helped to explain the dramatic accumulation of neutrophils at the symptomatic serosal sites; the wild-type gene likely acts as an upregulator of an anti-inflammatory molecule or as a downregulator of a pro-inflammatory molecule. For nearly half a century, FMF was thought to cluster primarily in non-Ashkenazi Jews, Arabs, Armenians, and Turks, although the screening of the 8 known mutations in an American cohort has identified substantial numbers of people from the Ashkenazi Jewish and Italian populations in the United States who also have this disease. Nevertheless, the symptoms often go unrecognized and patients remain undiagnosed for years, not receiving the highly efficacious colchicine therapy; their histories often include multiple laparotomies, laparoscopies, and psychiatric evaluations. The combinations of clinical manifestations among FMF patients are quite heterogeneous, but our American cohort did not establish any connections between individual mutations and specific clinical pictures--as is seen in other diseases like cystic fibrosis, in which distinct genotypes target certain organ systems. Specifically, the data from our American series are insufficient to evaluate the hypothesis that the M694V/M694V genotype confers a more severe phenotype, or increases the risk of amyloidosis; but both our data and the recent literature (160) indicate that amyloidosis can occur in FMF patients with only 1 copy, or no copies, of the M694V mutation. It appears that specific MEFV mutations are probably not the sole determinants of phenotype, and that unknown environmental factors or modifying genes act as accomplices in this disease. Although we hope the discovery of the FMF gene will allow the diagnosis of FMF to become genetically accurate, the reality is that both clinical and genetic tools must still be used together unless mutations are identified on both of a patient's chromosomes. Physicians should be careful not to rule out the diagnosis in patients of high-risk ethnic backgrounds just because of atypical clinical features, as our data indicate that MEFV mutations are sometimes demonstrable in such patients. At the same time, physicians cannot yet rely solely on a genetic diagnosis because we have not yet identified a sufficient spectrum of mutations, and it is not currently feasible to examine every patient's full DNA sequence for the entire gene; screening an ethnically consistent and clinically positive patient for the 8 known mutations frequently identifies a mutation on only 1 chromosome, and genetic analysis of other classic cases will often reveal none of the 8 mutations. Still, our data suggest that ethnic background is an important predictor of finding 1 of the presently known mutations, and the knowledge of ancestries atypical for FMF can suggest the diagnosis of other hereditary periodic fever syndromes. As the list of FMF-associated MEFV mutations is expanded, and/or new sequencing technologies permit more rapid screening, the value and interpretation of genetic testing for FMF will become more straightforward. Moreover, as the pathophysiology of this disorder becomes less of a hypothesis and more of an understood entity, it is likely that treatment options will broaden beyond the use of daily prophylactic colchicine. (ABSTRACT TRUNCATED)

A high-resolution genetic map of the familial Mediterranean fever candidate region allows identification of haplotype-sharing among ethnic groups

Familial Mediterranean fever (FMF) is a recessive disorder of inflammation caused by mutations in a gene (designated MEFV) on chromosome 16p13.3. We have recently constructed a 1-Mb cosmid contig that includes the FMF critical region. Here we show genotype data for 12 markers from our physical map, including 5 newly identified microsatellites, in FMF families. Intrafamilial recombinations placed MEFV in the approximately 285 kb between D16S468/D16S3070 and D16S3376. We observed significant linkage disequilibrium in the North African Jewish population, and historical recombinants in the founder haplotype placed MEFV between D16S3082 and D16S3373 (approximately 200 kb). In smaller panels of Iraqi Jewish, Arab, and Armenian families, there were significant allelic associations only for D16S3370 and D16S2617 among the Armenians. A sizable minority of Iraqi Jewish and Armenian carrier chromosomes appeared to be derived from the North African Jewish ancestral haplotype. We observed a unique FMF haplotype common to Iraqi Jews, Arabs, and Armenians and two other haplotypes restricted to either the Iraqi Jewish or the Armenian population. These data support the view that a few major mutations account for a large percentage of the cases of FMF and suggest that some of these mutations arose before the affected Middle Eastern populations diverged from one another.

Construction of a 1-Mb restriction-mapped cosmid contig containing the candidate region for the familial Mediterranean fever locus (MEFV) on chromosome 16p 13.3

In this paper we describe the assembly and restriction map of a 1.05-Mb cosmid contig spanning the candidate region for familial Mediterranean fever (FMF), a recessively inherited disorder of inflammation localized to 16p13.3. Using a combination of cosmid walking and screening for P1, PAC, BAC, and YAC clones, we have generated a contig of genomic clones spanning approximately 1050 kb that contains the FMF critical region. The map consists of 179 cosmid, 15 P1, 10 PAC, 3 BAC, and 17 YAC clones, anchored by 27 STS markers. Eight additional STSs have been developed from the approximately 700 kb immediately centromeric to this genomic region. Five of the 35 STSs are microsatellites that have not been previously reported. NotI and EcoRI mapping of the overlapping cosmids, hybridization of restriction fragments from cosmids to one another, and STS analyses have been used to validate the assembly of the contig. Our contig totally subsumes the 250-kb interval recently reported, by founder haplotype analysis, to contain the FMF gene. Thus, our high-resolution clone map provides an ideal resource for transcriptional mapping toward the eventual identification of this disease gene.

Production of anti-erythrocyte antibodies by leukemic and nonleukemic B cells in chronic lymphocytic leukemia patients

We have assessed the specificity of antibodies from the leukemic B cells of five patients with both chronic lymphocytic leukemia and autoimmune hemolytic anemia (CLL-AHA). Leukemic cells from one patient displayed surface immunoglobulin with heavy and light chain isotypes identical to that of the patient's anti-red blood cell (RBC) antibodies, and the leukemic cells secreted antibodies in vitro with anti-RBC activity. However, in the remaining patients, the leukemic cells displayed surface immunoglobulin with light chain isotypes different from that of the patient's anti-RBC antibodies and secreted antibodies in vitro with no detectable anti-RBC activity. Thus, there are two distinct classes of CLL-AHA patients, differentiated by the presence or absence of an anti-RBC antibody-producing leukemic B cell clone. The apparent heterogeneity in the source of pathogenic anti-RBC antibodies may impact the treatment response of the two classes of CLL-AHA patients.

Cloning and characterization of centromeric DNA from Neurospora crassa

The centromere locus from linkage group VII of Neurospora crassa has been cloned, characterized, and physically mapped. The centromeric DNA is contained within a 450-kb region that is recombination deficient, A+T-rich, and contains repetitive sequences. Repetitive sequences from within this region hybridize to a family of repeats located at or near centromeres in all seven linkage groups of N. crassa. Genomic Southern blots and sequence analysis of these repeats revealed a unique centromere structure containing a divergent family of centromere-specific repeats. The predominantly transitional differences between copies of the centromere-specific sequence repeats and their high A+T content suggest that their divergence was mediated by repeat-induced point (RIP) mutations.